A 17-Year-Old Male with Pain and Swelling in His Thumb

Differential Diagnosis

• Adductor pollicis tendon rupture
• Arthritic disease of the metacarpophalangeal joint
• Intra articular fracture of the ulnar base of the proximal phalanx
• Displaced intra articular fracture of the ulnar base of the proximal phalanx of the first digit
• Metacarpophalangeal dislocation

Diagnosis

This patient has a mildly displaced intra articular fracture of the ulnar base of the proximal phalanx of the first digit, also known as a gamekeeper’s fracture—so called because, in an earlier time, the repetitive breaking of the necks of small game resulted in chronic injury to the ulnar collateral ligament of the metacarpophalangeal joint of the thumb. This is similar to skier’s thumb, a reference to injury in which the ski pole or strap forcibly abducts the thumb during a fall or particularly aggressive pole-plant.

Learnings/What to Look for

• Determining mechanism of injury is critical for diagnosis of a gamekeeper’s fracture
• Pain on palpation, bruising, and swelling are common signs
• The most frequent site of injury is at the attachment of the ligament to the proximal phalanx; a bony avulsion occurs in approximately 50% of injuries

Pearls for Urgent Care Management and Considerations for Transfer

• If the joint is stable, immobilization for 4 weeks in a cast or splint is warranted
• If the joint is not stable, refer to an orthopedist